… | |
… | |
363 | might affect timers and time-outs. |
363 | might affect timers and time-outs. |
364 | |
364 | |
365 | When this is the case, you can call this method, which will update the |
365 | When this is the case, you can call this method, which will update the |
366 | event loop's idea of "current time". |
366 | event loop's idea of "current time". |
367 | |
367 | |
|
|
368 | A typical example would be a script in a web server (e.g. C<mod_perl>) - |
|
|
369 | when mod_perl executes the script, then the event loop will have the wrong |
|
|
370 | idea about the "current time" (being potentially far in the past, when the |
|
|
371 | script ran the last time). In that case you should arrange a call to C<< |
|
|
372 | AnyEvent->now_update >> each time the web server process wakes up again |
|
|
373 | (e.g. at the start of your script, or in a handler). |
|
|
374 | |
368 | Note that updating the time I<might> cause some events to be handled. |
375 | Note that updating the time I<might> cause some events to be handled. |
369 | |
376 | |
370 | =back |
377 | =back |
371 | |
378 | |
372 | =head2 SIGNAL WATCHERS |
379 | =head2 SIGNAL WATCHERS |
… | |
… | |
395 | correctly. |
402 | correctly. |
396 | |
403 | |
397 | Example: exit on SIGINT |
404 | Example: exit on SIGINT |
398 | |
405 | |
399 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
406 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
|
|
407 | |
|
|
408 | =head3 Restart Behaviour |
|
|
409 | |
|
|
410 | While restart behaviour is up to the event loop implementation, most will |
|
|
411 | not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's |
|
|
412 | pure perl implementation). |
|
|
413 | |
|
|
414 | =head3 Safe/Unsafe Signals |
|
|
415 | |
|
|
416 | Perl signals can be either "safe" (synchronous to opcode handling) or |
|
|
417 | "unsafe" (asynchronous) - the former might get delayed indefinitely, the |
|
|
418 | latter might corrupt your memory. |
|
|
419 | |
|
|
420 | AnyEvent signal handlers are, in addition, synchronous to the event loop, |
|
|
421 | i.e. they will not interrupt your running perl program but will only be |
|
|
422 | called as part of the normal event handling (just like timer, I/O etc. |
|
|
423 | callbacks, too). |
400 | |
424 | |
401 | =head3 Signal Races, Delays and Workarounds |
425 | =head3 Signal Races, Delays and Workarounds |
402 | |
426 | |
403 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
427 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
404 | callbacks to signals in a generic way, which is a pity, as you cannot |
428 | callbacks to signals in a generic way, which is a pity, as you cannot |
… | |
… | |
592 | after => 1, |
616 | after => 1, |
593 | cb => sub { $result_ready->send }, |
617 | cb => sub { $result_ready->send }, |
594 | ); |
618 | ); |
595 | |
619 | |
596 | # this "blocks" (while handling events) till the callback |
620 | # this "blocks" (while handling events) till the callback |
597 | # calls -<send |
621 | # calls ->send |
598 | $result_ready->recv; |
622 | $result_ready->recv; |
599 | |
623 | |
600 | Example: wait for a timer, but take advantage of the fact that condition |
624 | Example: wait for a timer, but take advantage of the fact that condition |
601 | variables are also callable directly. |
625 | variables are also callable directly. |
602 | |
626 | |
… | |
… | |
666 | one. For example, a function that pings many hosts in parallel might want |
690 | one. For example, a function that pings many hosts in parallel might want |
667 | to use a condition variable for the whole process. |
691 | to use a condition variable for the whole process. |
668 | |
692 | |
669 | Every call to C<< ->begin >> will increment a counter, and every call to |
693 | Every call to C<< ->begin >> will increment a counter, and every call to |
670 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
694 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
671 | >>, the (last) callback passed to C<begin> will be executed. That callback |
695 | >>, the (last) callback passed to C<begin> will be executed, passing the |
672 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
696 | condvar as first argument. That callback is I<supposed> to call C<< ->send |
673 | callback was set, C<send> will be called without any arguments. |
697 | >>, but that is not required. If no group callback was set, C<send> will |
|
|
698 | be called without any arguments. |
674 | |
699 | |
675 | You can think of C<< $cv->send >> giving you an OR condition (one call |
700 | You can think of C<< $cv->send >> giving you an OR condition (one call |
676 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
701 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
677 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
702 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
678 | |
703 | |
… | |
… | |
705 | begung can potentially be zero: |
730 | begung can potentially be zero: |
706 | |
731 | |
707 | my $cv = AnyEvent->condvar; |
732 | my $cv = AnyEvent->condvar; |
708 | |
733 | |
709 | my %result; |
734 | my %result; |
710 | $cv->begin (sub { $cv->send (\%result) }); |
735 | $cv->begin (sub { shift->send (\%result) }); |
711 | |
736 | |
712 | for my $host (@list_of_hosts) { |
737 | for my $host (@list_of_hosts) { |
713 | $cv->begin; |
738 | $cv->begin; |
714 | ping_host_then_call_callback $host, sub { |
739 | ping_host_then_call_callback $host, sub { |
715 | $result{$host} = ...; |
740 | $result{$host} = ...; |
… | |
… | |
941 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
966 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
942 | if it is defined then the event loop has already been detected, and the |
967 | if it is defined then the event loop has already been detected, and the |
943 | array will be ignored. |
968 | array will be ignored. |
944 | |
969 | |
945 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
970 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
946 | it,as it takes care of these details. |
971 | it, as it takes care of these details. |
947 | |
972 | |
948 | This variable is mainly useful for modules that can do something useful |
973 | This variable is mainly useful for modules that can do something useful |
949 | when AnyEvent is used and thus want to know when it is initialised, but do |
974 | when AnyEvent is used and thus want to know when it is initialised, but do |
950 | not need to even load it by default. This array provides the means to hook |
975 | not need to even load it by default. This array provides the means to hook |
951 | into AnyEvent passively, without loading it. |
976 | into AnyEvent passively, without loading it. |
|
|
977 | |
|
|
978 | Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used |
|
|
979 | together, you could put this into Coro (this is the actual code used by |
|
|
980 | Coro to accomplish this): |
|
|
981 | |
|
|
982 | if (defined $AnyEvent::MODEL) { |
|
|
983 | # AnyEvent already initialised, so load Coro::AnyEvent |
|
|
984 | require Coro::AnyEvent; |
|
|
985 | } else { |
|
|
986 | # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent |
|
|
987 | # as soon as it is |
|
|
988 | push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; |
|
|
989 | } |
952 | |
990 | |
953 | =back |
991 | =back |
954 | |
992 | |
955 | =head1 WHAT TO DO IN A MODULE |
993 | =head1 WHAT TO DO IN A MODULE |
956 | |
994 | |
… | |
… | |
1105 | |
1143 | |
1106 | package AnyEvent; |
1144 | package AnyEvent; |
1107 | |
1145 | |
1108 | # basically a tuned-down version of common::sense |
1146 | # basically a tuned-down version of common::sense |
1109 | sub common_sense { |
1147 | sub common_sense { |
1110 | # no warnings |
1148 | # from common:.sense 1.0 |
1111 | ${^WARNING_BITS} ^= ${^WARNING_BITS}; |
1149 | ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; |
1112 | # use strict vars subs |
1150 | # use strict vars subs |
1113 | $^H |= 0x00000600; |
1151 | $^H |= 0x00000600; |
1114 | } |
1152 | } |
1115 | |
1153 | |
1116 | BEGIN { AnyEvent::common_sense } |
1154 | BEGIN { AnyEvent::common_sense } |
1117 | |
1155 | |
1118 | use Carp (); |
1156 | use Carp (); |
1119 | |
1157 | |
1120 | our $VERSION = 4.92; |
1158 | our $VERSION = '5.22'; |
1121 | our $MODEL; |
1159 | our $MODEL; |
1122 | |
1160 | |
1123 | our $AUTOLOAD; |
1161 | our $AUTOLOAD; |
1124 | our @ISA; |
1162 | our @ISA; |
1125 | |
1163 | |
1126 | our @REGISTRY; |
1164 | our @REGISTRY; |
1127 | |
|
|
1128 | our $WIN32; |
|
|
1129 | |
1165 | |
1130 | our $VERBOSE; |
1166 | our $VERBOSE; |
1131 | |
1167 | |
1132 | BEGIN { |
1168 | BEGIN { |
1133 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
1169 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
… | |
… | |
1342 | |
1378 | |
1343 | package AnyEvent::Base; |
1379 | package AnyEvent::Base; |
1344 | |
1380 | |
1345 | # default implementations for many methods |
1381 | # default implementations for many methods |
1346 | |
1382 | |
1347 | sub _time { |
1383 | sub _time() { |
1348 | # probe for availability of Time::HiRes |
1384 | # probe for availability of Time::HiRes |
1349 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1385 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1350 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1386 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1351 | *_time = \&Time::HiRes::time; |
1387 | *_time = \&Time::HiRes::time; |
1352 | # if (eval "use POSIX (); (POSIX::times())... |
1388 | # if (eval "use POSIX (); (POSIX::times())... |
… | |
… | |
1372 | |
1408 | |
1373 | our $HAVE_ASYNC_INTERRUPT; |
1409 | our $HAVE_ASYNC_INTERRUPT; |
1374 | |
1410 | |
1375 | sub _have_async_interrupt() { |
1411 | sub _have_async_interrupt() { |
1376 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1412 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1377 | && eval "use Async::Interrupt 1.0 (); 1") |
1413 | && eval "use Async::Interrupt 1.02 (); 1") |
1378 | unless defined $HAVE_ASYNC_INTERRUPT; |
1414 | unless defined $HAVE_ASYNC_INTERRUPT; |
1379 | |
1415 | |
1380 | $HAVE_ASYNC_INTERRUPT |
1416 | $HAVE_ASYNC_INTERRUPT |
1381 | } |
1417 | } |
1382 | |
1418 | |
… | |
… | |
1385 | our ($SIG_COUNT, $SIG_TW); |
1421 | our ($SIG_COUNT, $SIG_TW); |
1386 | |
1422 | |
1387 | sub _signal_exec { |
1423 | sub _signal_exec { |
1388 | $HAVE_ASYNC_INTERRUPT |
1424 | $HAVE_ASYNC_INTERRUPT |
1389 | ? $SIGPIPE_R->drain |
1425 | ? $SIGPIPE_R->drain |
1390 | : sysread $SIGPIPE_R, my $dummy, 9; |
1426 | : sysread $SIGPIPE_R, (my $dummy), 9; |
1391 | |
1427 | |
1392 | while (%SIG_EV) { |
1428 | while (%SIG_EV) { |
1393 | for (keys %SIG_EV) { |
1429 | for (keys %SIG_EV) { |
1394 | delete $SIG_EV{$_}; |
1430 | delete $SIG_EV{$_}; |
1395 | $_->() for values %{ $SIG_CB{$_} || {} }; |
1431 | $_->() for values %{ $SIG_CB{$_} || {} }; |
… | |
… | |
1911 | warn "read: $input\n"; # output what has been read |
1947 | warn "read: $input\n"; # output what has been read |
1912 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1948 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1913 | }, |
1949 | }, |
1914 | ); |
1950 | ); |
1915 | |
1951 | |
1916 | my $time_watcher; # can only be used once |
|
|
1917 | |
|
|
1918 | sub new_timer { |
|
|
1919 | $timer = AnyEvent->timer (after => 1, cb => sub { |
1952 | my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub { |
1920 | warn "timeout\n"; # print 'timeout' about every second |
1953 | warn "timeout\n"; # print 'timeout' at most every second |
1921 | &new_timer; # and restart the time |
|
|
1922 | }); |
1954 | }); |
1923 | } |
|
|
1924 | |
|
|
1925 | new_timer; # create first timer |
|
|
1926 | |
1955 | |
1927 | $cv->recv; # wait until user enters /^q/i |
1956 | $cv->recv; # wait until user enters /^q/i |
1928 | |
1957 | |
1929 | =head1 REAL-WORLD EXAMPLE |
1958 | =head1 REAL-WORLD EXAMPLE |
1930 | |
1959 | |
… | |
… | |
2374 | As you can see, the AnyEvent + EV combination even beats the |
2403 | As you can see, the AnyEvent + EV combination even beats the |
2375 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2404 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2376 | backend easily beats IO::Lambda and POE. |
2405 | backend easily beats IO::Lambda and POE. |
2377 | |
2406 | |
2378 | And even the 100% non-blocking version written using the high-level (and |
2407 | And even the 100% non-blocking version written using the high-level (and |
2379 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a |
2408 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda |
2380 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
2409 | higher level ("unoptimised") abstractions by a large margin, even though |
2381 | in a non-blocking way. |
2410 | it does all of DNS, tcp-connect and socket I/O in a non-blocking way. |
2382 | |
2411 | |
2383 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2412 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2384 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2413 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2385 | part of the IO::lambda distribution and were used without any changes. |
2414 | part of the IO::Lambda distribution and were used without any changes. |
2386 | |
2415 | |
2387 | |
2416 | |
2388 | =head1 SIGNALS |
2417 | =head1 SIGNALS |
2389 | |
2418 | |
2390 | AnyEvent currently installs handlers for these signals: |
2419 | AnyEvent currently installs handlers for these signals: |
… | |
… | |
2432 | it's built-in modules) are required to use it. |
2461 | it's built-in modules) are required to use it. |
2433 | |
2462 | |
2434 | That does not mean that AnyEvent won't take advantage of some additional |
2463 | That does not mean that AnyEvent won't take advantage of some additional |
2435 | modules if they are installed. |
2464 | modules if they are installed. |
2436 | |
2465 | |
2437 | This section epxlains which additional modules will be used, and how they |
2466 | This section explains which additional modules will be used, and how they |
2438 | affect AnyEvent's operetion. |
2467 | affect AnyEvent's operation. |
2439 | |
2468 | |
2440 | =over 4 |
2469 | =over 4 |
2441 | |
2470 | |
2442 | =item L<Async::Interrupt> |
2471 | =item L<Async::Interrupt> |
2443 | |
2472 | |
… | |
… | |
2448 | catch the signals) with some delay (default is 10 seconds, look for |
2477 | catch the signals) with some delay (default is 10 seconds, look for |
2449 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2478 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2450 | |
2479 | |
2451 | If this module is available, then it will be used to implement signal |
2480 | If this module is available, then it will be used to implement signal |
2452 | catching, which means that signals will not be delayed, and the event loop |
2481 | catching, which means that signals will not be delayed, and the event loop |
2453 | will not be interrupted regularly, which is more efficient (And good for |
2482 | will not be interrupted regularly, which is more efficient (and good for |
2454 | battery life on laptops). |
2483 | battery life on laptops). |
2455 | |
2484 | |
2456 | This affects not just the pure-perl event loop, but also other event loops |
2485 | This affects not just the pure-perl event loop, but also other event loops |
2457 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2486 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2458 | |
2487 | |
… | |
… | |
2479 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2508 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2480 | purely used for performance. |
2509 | purely used for performance. |
2481 | |
2510 | |
2482 | =item L<JSON> and L<JSON::XS> |
2511 | =item L<JSON> and L<JSON::XS> |
2483 | |
2512 | |
2484 | This module is required when you want to read or write JSON data via |
2513 | One of these modules is required when you want to read or write JSON data |
2485 | L<AnyEvent::Handle>. It is also written in pure-perl, but can take |
2514 | via L<AnyEvent::Handle>. It is also written in pure-perl, but can take |
2486 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2515 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2487 | |
2516 | |
2488 | In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is |
2517 | In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is |
2489 | installed. |
2518 | installed. |
2490 | |
2519 | |
… | |
… | |
2508 | |
2537 | |
2509 | Most event libraries are not fork-safe. The ones who are usually are |
2538 | Most event libraries are not fork-safe. The ones who are usually are |
2510 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2539 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2511 | calls. Only L<EV> is fully fork-aware. |
2540 | calls. Only L<EV> is fully fork-aware. |
2512 | |
2541 | |
|
|
2542 | This means that, in general, you cannot fork and do event processing |
|
|
2543 | in the child if a watcher was created before the fork (which in turn |
|
|
2544 | initialises the event library). |
|
|
2545 | |
2513 | If you have to fork, you must either do so I<before> creating your first |
2546 | If you have to fork, you must either do so I<before> creating your first |
2514 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2547 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2515 | something completely out of the scope of AnyEvent. |
2548 | something completely out of the scope of AnyEvent. |
|
|
2549 | |
|
|
2550 | The problem of doing event processing in the parent I<and> the child |
|
|
2551 | is much more complicated: even for backends that I<are> fork-aware or |
|
|
2552 | fork-safe, their behaviour is not usually what you want: fork clones all |
|
|
2553 | watchers, that means all timers, I/O watchers etc. are active in both |
|
|
2554 | parent and child, which is almost never what you want. |
2516 | |
2555 | |
2517 | |
2556 | |
2518 | =head1 SECURITY CONSIDERATIONS |
2557 | =head1 SECURITY CONSIDERATIONS |
2519 | |
2558 | |
2520 | AnyEvent can be forced to load any event model via |
2559 | AnyEvent can be forced to load any event model via |